Starship development and progress [previous title: Will Musk's starship reach orbit this year?]

Apparently the launch stand did take damage again.

I think everything SpaceX does can be put on a sliding scale between “we worked really, really hard on this to get it absolutely perfect” and “eh, looks like a 50/50 shot–send it!” And that reentry and a few other things were closer to the far end of that scale. They have limited resources and put those on the things that matter most for making forward progress–here, making orbit, and getting the booster to survive boostback. Other stuff is more of a nice-to-have.

SpaceX posted a short summary here:

One notable bit:

Starship did not attempt its planned on-orbit relight of a single Raptor engine due to vehicle roll rates during coast

I think we can infer from that that they didn’t have full attitude control in the coast phase, which is consistent with what we saw. I didn’t see any reaction control thruster action happening. And that would have affected reentry as well. Hopefully we find out more details eventually.

Yeah, I think RCS failed. Was this flight one where they were going to try using ullage gas for RCS?

Is there any confirmation that the venting we saw was the intended venting of LOX? Or was that a leak of some sort? If the latter, maybe it depressurized the RCS system.

The door design looked strange to me, and it didn’t seem to perform very well. Also, I wonder how much residual pressure it has to deal with? Starship may not be gas-tight, but that’s a large volume and it would take some time to reach vacuum unless it was seriously vented.

As for the booster, if the gauges onscreen are correct it looked like they might have run out of LOX. When they tried to relight they got a few started in an asymmetric pattern then they went out.

But these are nitpicks. They closed out all the failures they had last time, and both vehicles did the hot staging fine, etc. SpaceX already now has the largest launch system in history. The next task is to make it reusable. But even if it takes a long time to get the landings right, they now have the capacity to send 150 tons to LEO in expendable mode.

I think prop starvation due to uncontrolled roll is much more likely. There was something wrong with the way the grid fins were operating and the whole vehicle was oscillating pretty rapidly.

I wouldn’t really expect the gauges to be correct. The booster has a header tank for the LOX, and for the methane is depending largely on the volume of the downcomer. I don’t think those would necessarily be tracked properly by the gauges they show.

Here’s where we’re at without Starship:
Imgur

If the competition doesn’t heat up soon, every one of their competitors will have to live in the little inset box due to only occupying a few pixels.

I can’t be the only person who thinks that maybe, just maybe, as much as people want to go back to the moon, we aren’t supposed to do that.

People who don’t want to go to the moon don’t have to.

I think humanity has a moral obligation to expand to the solar system and eventually the stars. A universe without life to observe it is a dead, worthless thing. And life of any kind needs humanity to carry it off this one fragile rock.

What does “supposed to” even mean in this context?

I can only guess what nearwildheaven meant, but it seems to me it is a metaphor, like when Dr.Strangelove writes “humanity has a moral obligation” or “a universe without life [is a] worthless thing”. I think they are valid arguments even if I disagree with all three statements.

You do realize the two halves of your sentence don’t go together?

“Usually” implies the chance is not equal to zero. “Zero” implies “usually” should be “always”.

So which did you believe before they launched on time? :wink:


Unrelated to the above ...

Good bet @nearwildheaven is making a reference to something akin to the humorous Great Galactic Ghoul who is posited to defend Mars from earth-based probes by making them fail in ever more unexpected ways. See Exploration of Mars - Wikipedia for more.

In other words …

Well the name is “nearwildheaven”, not “enterwildheaven”.

You know when you want to do or have something, and efforts to do or obtain them keep falling through, and you explain it by saying, “Guess I wasn’t supposed to have/do that”? That’s what I mean.

While I recognize the sentiment, I think in this case (as in my personal real-life instances of this), the more appropriate version is “looks like I’m not supposed to have this… yet.”

This wasn’t a failure, and certainly wasn’t a reason to quit.

FWIW, the Apollo 11 landing happened just days before I started kindergarten, and I mainly remember being allowed to eat breakfast in the living room so I could watch it.

As a young’un, one of the things I wanted to be when I grew up was the first woman on the moon, after finding out that I could not be the first woman in space. (That happened before I was born, with Valentina Tereshkova.) Technically, I still could be.

Good thing we didn’t give up after the Apollo 1 cabin fire. And that killed three people–it wasn’t just destroyed equipment.

I should really have known that name. But I am amused now, because Kerbal Space Program 2 has a girl-Kerbal as its protagonist, named… Valentina Kerman. Clearly named after Valentina Tereshkova.

I remember reading a lot of science fiction of that era that presumed that female cosmonauts were going to be regular thing; that the Soviet Union actually believed its own rhetoric about male-female equality. Turned out the leadership did it purely as a propaganda stunt and afterwards had zero interest in letting women fly space missions.

One funny-but-true thing that Robert Zubrin brings up occasionally–if we’re going to Mars, we should really be picking small people. For the same resources, you can have three 133 lb people or two 200 lb people. That’s a 50% improvement in capability–maybe a 100% improvement if we assume that one person is dedicated to basic operational tasks. And women tend to be smaller than men.

I’m not sure resources needed scale directly to body weight like that. For starters the oxygen requirements of our brains are pretty inflexible, there’s no way to economize on that. For food and water I’d have to research what calorie requirements by body weight are recommended but I’d be surprised if it scaled at 1:1.

There are all kinds of base metabolic rate equations, but the Katch-McArdle formula is just:
BMR = 370 + 21.6(1 - F)W

F is body fat proportion. W is weight. So there’s a 370 calorie baseline, but the rest scales with weight. And women are likely to have a higher fat proportion, decreasing that part of the formula.

Overall, it should be pretty close to a linear scaling. Especially taking into account non-base metabolic needs. Water, heating (or cooling), etc. needs are going to scale with metabolism as well.